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Discussion Starter #1
I have the rear drum off, and plan to replace shoes and wheel cylinder.

Any idea how tight the big nut needs to be? I checked all 3 of my books none listed torque, and one says "full tight". But if you have to get that cotter pin through, I am not sure if that "full tight" means anything. Am I supposed to tighten this until a certain torque and then back off to alight the cotter pin?

Thanks
 

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After a ton of research I found there was no answer, just opinions. I snugged mine on and advanced them to the next alignment hole. Advancing to the next hole actually produced a fair amount of torque. I haven't taken the drums off again, but no wobbles or wear problems.
 

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After a ton of research I found there was no answer, just opinions. I snugged mine on and advanced them to the next alignment hole. Advancing to the next hole actually produced a fair amount of torque. I haven't taken the drums off again, but no wobbles or wear problems.
Right on - just opinions. Try your search in Swedish for even more opinions!

My opinion on Volvos with rear drum brakes (castle nut torque)...

The axle/hub (drum)/brake components MUST be correctly assembled (that guide pin key will fit many ways but only one is correct).

The brake shoe adjustment must be fully "inward".

The caste nut, washer, axle (half-shaft) and axle threads must not be damaged in any way.

Once all is together properly tighten the caste nut "fully", back off to the first cotter pin hole, insert a NEW cotter pin (bent correctly), adjust the brake shoes and hand brake action, mount the wheel and tire then drive the car briefly.

If the car can not be driven just lower the tire to the floor to put weight on the axle. If this is not practical just spin the wheel a few times to check for looseness/wobble, etc.

Once the car has been driven a few miles raise the back axle, confirm that the brake shoes are not dragging (hand brake action also), remove the wheel/tire and cotter pin, tighten the castle nut "fully" if needed, back off to first cotter pin hole, correctly install a NEW cotter pin, adjust brakes as needed, re-assemble everything.

20,000 miles later - repeat.

George Dill
 

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Discussion Starter #6
So, George, the big nut is not supposed to be all out tight ....

Question. Are these drums self adjusting? When you slam on the brakes in reverse, does this expand the shoes? My screw driver is a bit long, and interferes with some other components on the diff, and cannot get in there (I don't remember what parts was the interference, but it may have been the rear sway bar).

If I can find a short screw driver, may be I can get in there. But does anybody remember which way the star wheel needs to spin to tighten? This is the left rear. Yes, I had the thing on my hands today, but forgot to take note.

Just got the new wheel cylinder and shows in there.

Thanks
 

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So, George, the big nut is not supposed to be all out tight ....

Question. Are these drums self adjusting? When you slam on the brakes in reverse, does this expand the shoes? My screw driver is a bit long, and interferes with some other components on the diff, and cannot get in there (I don't remember what parts was the interference, but it may have been the rear sway bar).

If I can find a short screw driver, may be I can get in there. But does anybody remember which way the star wheel needs to spin to tighten? This is the left rear. Yes, I had the thing on my hands today, but forgot to take note.

Just got the new wheel cylinder and shows in there.

Thanks
The castle nut just keeps the hub from falling off the halfshaft - the tapered fit and properly-installed key maintain the proper axle-hub relationship.

If your '67 Amazon rear drum brake has a star-wheel adjustment then the car may not be a '67...

http://www.skandix.de/en/spare-parts/brakes/drum-brake/adjuster-drum-brake-rear-axle/1017731/

http://www.skandix.de/en/spare-parts/brakes/drum-brake/adjuster-drum-brake-rear-axle/1018310/

http://www.skandix.de/en/spare-parts/brakes/drum-brake/adjuster-drum-brake-rear-axle/1018311/

George Dill
 

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Discussion Starter #8
The pictures of the adjuster do not look familiar. The teeth on the adjustment wheel in the picture are asymmetrical, whereas mine looked symmetrical.

But there are two sets of brake drums for the 67, the Girling and the Wagner. They have different shoes and different wheel cylinders. I ordered from IPD my shoes and wheel cylinder, which did fit properly (I thik it was the Wagner, the small wheel cylinder). The shows were also identical, and fit well. So, I think that the setup is correct for the car. I have a few pictures, before and after the shoe replacement. I will send that to you George if I find your email address.

Anybody else knows which way to spin the star wheel to tighten? I got the drum on, and at first it felt very tight to spin by hand. Then, I started the engine, and span the drum a bit on first gear. It loosened up, to the extend that I could turn by hand. So, it may be OK, but the hand brake will not hold the drum (it may have been that way before, and may be the hand brake catches the right side). Also, if this is self adjusting brakes, may be I don't need to worry about, it will adjust itself in reverse. Yes? No?
 

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Discussion Starter #9
On the nut case. ;) I guess once you tightened the big nut and the drum is pressed on the shaft, you do not need to maintain the high compression on the nut, and just a light load will hold it together. I will back out the nut to the first opening and install a new cotter pin. Any idea what size this cotter pin is? Looked like 1/8?
 

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I recall reading somewhere (possibly a shop manual) that the minimum nut torque on the rear axles is supposed to be 100 lb-ft. What I do is install the nut and washer, torque to 100 lb-ft, and then advance to the next place on the castle nut where the cotter pin will go through.

If you run the torque calculations for that thread pitch and diameter, 100 lb ft is a pretty light torque. I could break out my calculator and calculate the maximum possible torque given angle of turn and thread pitch for the maximum possible cotter pin hole misalignment, but at the end of the day, I've never had a drum fall off, or damaged anything, so I'm satisfied.

Always make sure the drum and axle tapered surfaces are perfectly clean. I typically coat both with a light layer of anti-seize. I have heard other say not to do so, that the integrity of the joint lies within the direct metal-on-metal contact of the tapered axle/ drum. However, I have had numerous stuck drum/ axle situations I've encountered with tapered axles, but never again after using anti-seize- and again, never noted any issues with installing components in that manner.
 

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Also, I do not believe the rear drums are self-adjusting. You need to do that manually. I know the right side and left side wheel adjusters typically have opposite threads, so you have to mess with them before you put them in and check whether CW tightens the shoes on that side or CCW. Its the sort of thing I always re-teach myself when doing a brake job, and then promptly forget afterwards.
 

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Nut case - I'm still here.

Yes, it is self-adjusting and yes this function will not work properly unless all components are assembled just so AND the hand brake is correctly assembled/adjusted.

Your adjuster...
----------------------------------------------------------------------
Brake adjuster star wheel style AZ 1959-61 with front drums; AZ late 1967-68 with dual circuit master cylinder…

http://www.swedishtreasures.com/659665.jpg

---------------------------------------------------------------------

...and the answers (with pics) to all your questions except one...

http://www.google.com/search?hl=en&...=any&safe=images&tbs=&as_filetype=&as_rights=

Cotter pin size?

Here is the length...

http://volvoklassiekeronderdelen.nl/shopping/images/Volvo_191174.JPG

...and now, your being an engineer/mathematician, determine the OD of the split pin using this same picture.

George Dill
 

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On the nut case. ;) I guess once you tightened the big nut and the drum is pressed on the shaft, you do not need to maintain the high compression on the nut, and just a light load will hold it together. I will back out the nut to the first opening and install a new cotter pin. Any idea what size this cotter pin is? Looked like 1/8?
Good guess - and correct.

George Dill
 

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Discussion Starter #15
Thanks all. Yes George, that was my adjustor (the picture on the website), only mine is not as clean.

I neglected cleaning the surfaces as Mike suggested, but I am not taking that drum off again! ;) I guess I am thinking "outside the box"! ')

I think the brakes are very close as I assembled them. I will bleed the brakes first, and see how it feels. If the car feels too soft, I will try a bit of reverse, and see how that works. If not, I will have to find a short screw driver and play with the star wheel, one way, then the other!

Working on drums is no fun. Fortunately, we don't have to do it often.
 

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Discussion Starter #16
I looked at my shop manual. It says that the star wheel spins clockwise to tighten. Great. Seen from the front or the rear ;)
 

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The last drums I did were on the front of a '49 Plymouth, and were not self-adjusting...must have confused those with the 122's rears. ;-)

The '49 Plymouth also has tapered rear axles/ drums. I have tried every imaginable trick to get them off, to no avail. My next try will be to remove the axle and soak each drum in a vat of old ATF or diesel fuel!
 

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The last drums I did were on the front of a '49 Plymouth, and were not self-adjusting...must have confused those with the 122's rears. ;-)

The '49 Plymouth also has tapered rear axles/ drums. I have tried every imaginable trick to get them off, to no avail. My next try will be to remove the axle and soak each drum in a vat of old ATF or diesel fuel!
Procedures for removing the rear drum brake (hub) from a '49 Plymouth are the same as the Volvo drums.

You will need a portable torch, 5lb hand sledge hammer, 5-lug hub puller, heavy gloves and eye protection.

Elevate and stabilize the diff, remove the hub cap, wheel/tire and axle nut/washer.

Reverse the axle (halfshaft) nut and replace it on the axle to protect the tip of the shaft.

Confirm that the brake shoes are fully retracted from the drums and the handbrake action is fully released. If needed, remove accessible components from the backing plate to force the shoes away from the drum.

Using the existing lug nuts (reversed), install the 5-lug hub puller so that every puller arm has exactly the same tension when the puller's threaded shaft is perfetly centered/parallel/perpendicular to the center tip of the halfshaft. This position is usually when each lug nut is flush with the end of the lug. Loosen the axle nut just enough to provide a shield should the puller center shaft displace.

Maintaining perfect puller alignment/tension tighten the puller center shaft with a large perfect-fit socket wrench. Leave the socket on the puller shaft and give it a single solid whack with the hammer. If the puller shaft can now be tightened more you have moved the hub a small amount. If not get out the torch and apply heat in suspected areas knowing that you are destroying the rubber components inside the hub.

Re-align/tighten everything as needed then whack again.

Repeat.

Remember to the keep the axle nut on the half shaft until the drum has exploded off the halfshaft and yes it will make a big pop.

Gather up all your materials, move everything to the other wheel then take a break while you get on the internet to sing praises to Swedespeed.

George Dill
 

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Or you can use a puller made like this:
<img src='http://dmz9xfeb9gm65.cloudfront.net/4053.jpg'/>
<img src='http://dmz9xfeb9gm65.cloudfront.net/4054.jpg'/>
<img src='http://dmz9xfeb9gm65.cloudfront.net/4055.jpg'/>
<img src='http://dmz9xfeb9gm65.cloudfront.net/4056.jpg'/>
and do ALL the pulling with the lugbolts.
If you get the lugbolts down all the way and haven't pulled far enough, you'll have to put a spacer inside it and go again.
I've used this on some MIGHTY tight axles and it has not failed me yet.
 

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Procedures for removing the rear drum brake (hub) from a '49 Plymouth are the same as the Volvo drums.

You will need a portable torch, 5lb hand sledge hammer, 5-lug hub puller, heavy gloves and eye protection.

Elevate and stabilize the diff, remove the hub cap, wheel/tire and axle nut/washer.

Reverse the axle (halfshaft) nut and replace it on the axle to protect the tip of the shaft.

Confirm that the brake shoes are fully retracted from the drums and the handbrake action is fully released. If needed, remove accessible components from the backing plate to force the shoes away from the drum.

Using the existing lug nuts (reversed), install the 5-lug hub puller so that every puller arm has exactly the same tension when the puller's threaded shaft is perfetly centered/parallel/perpendicular to the center tip of the halfshaft. This position is usually when each lug nut is flush with the end of the lug. Loosen the axle nut just enough to provide a shield should the puller center shaft displace.

Maintaining perfect puller alignment/tension tighten the puller center shaft with a large perfect-fit socket wrench. Leave the socket on the puller shaft and give it a single solid whack with the hammer. If the puller shaft can now be tightened more you have moved the hub a small amount. If not get out the torch and apply heat in suspected areas knowing that you are destroying the rubber components inside the hub.

Re-align/tighten everything as needed then whack again.

Repeat.

Remember to the keep the axle nut on the half shaft until the drum has exploded off the halfshaft and yes it will make a big pop.

Gather up all your materials, move everything to the other wheel then take a break while you get on the internet to sing praises to Swedespeed.

George Dill
Yep, did all that, drum would not come off. Car has been sitting since 1976. It runs and drives, but currently only has front brakes since I've been unable to remove the rear drums. Like I said, i tried about every trick I've learned from 10 years of pulling 122 rear drums off. This one's a stinker!
 
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